Average pH of surface waters in 1850 and 2100

Average pH of surface waters in 1850 vs its projected value in 2100 if current trends continue; CO2 emissions have increased ocean acidity by 26% since the beginning of the industrial revolution, by 2100 the acidity will have surged by 170%; as a result, many marine species will become extinct.

Average pH of surface waters in 1850 and 2100


- It's essential to note that the pH scale is logarithmic, i.e. a pH of 6 is ten times more acidic than a pH of 7 and 100 times more acidic than a pH of 8. That's why a decrease from 8.2 to 7.8 is a drastic change for the oceans.

- Why and how does ocean acidification happen? About 30% of the carbon dioxide emitted in the atmosphere is absorbed by the global ocean. Once CO2 meets the H2O, we get: 1. carbonic acid H2CO3 and 2. free hydrogen ions H+. Now, these free hydrogen ions H+ will bond with carbonate ions CO3(2-), which is bad, because carbonate ions are essential for the creation of calcium carbonate CaCO3, an essential ingredient for calcium based structures such as shells and coral. Basically too many H+ in the ocean, an effect of CO2 emissions, is stealing all the CO3(2-), which is fundamental for many marine species.

Acidification
Acidification


- Why is this important for humans? Around 70% (estimates vary from 50% to 85%) of the oxygen is produced by marine plants. Primarily by phytoplanktons. If ocean acidification continues, many species will suffer drastic consequences (some of them will inevitably become extinct), including phytoplanktons. Their balance will be greatly disturbed, many phytoplankton species will migrate and maybe adapt to the new conditions, others will probably dissapear. This will in turn reduce global oxygen levels. Fun fact: Phytoplankton population dropped by 40% since 1950.

Via  mit.edu & ocean-acidification.net
Share on Google Plus

Alex E

Ecoclimax is defined by Odum (1969) as the culmination state after a succession in a stabilized ecosystem in which maximum biomass (or high information content) and symbiotic function among organisms is kept per unit of available energy flow.